1. Field of the Invention
The present invention relates to a surveillance camera apparatus in which video data is obtained by photographing a scene of a surveillance area with a surveillance camera, a remote surveillance apparatus in which the scene of the surveillance area is reproduced from the video data at a remote location, and a remote surveillance system having the surveillance camera apparatus and the remote surveillance apparatus.
2. Description of the Related Art
In a department store or a shopping center, many customers go in and out. In this case, a surveillance camera is arranged in each surveillance area of the store or center, in which a large number of articles of commerce are arranged or a large amount of money is used, to always monitor the surveillance area, and a watchman always watches a monitor, on which a scene of the surveillance area is displayed, in a surveillance room. Therefore, many types of surveillance systems respectively having one surveillance camera and one monitor have been proposed.
2.1. First Previously Proposed Art
For example, a scene of a surveillance area placed in a department store or shopping center is photographed by a surveillance camera, and a monitor for displaying the scene of the surveillance area photographed by the surveillance camera is arranged in a surveillance room placed in the same department store or shopping center. In this case, the surveillance camera is connected to the monitor through a cable.
In this surveillance system, video data indicating a photographed scene image is transmitted from the surveillance camera to the monitor through the cable at a high speed, and the photographed scene image is displayed on the monitor at real time. Therefore, a watchman always watches the photographed scene image displayed on the monitor.
2.2. Problems to be Solved by the Invention
However, in the conventional surveillance system described above, it is required that a watchman always watches the photographed image displayed on the monitor. In this case, because it is required that the watchman carefully watches the photographed image while maintaining the power of his attention, the watching operation is a hard work for the watchman, so that the watchman easily becomes fatigued. Also, because it is required that the watchman always watches the photographed image, the watchman cannot do another work. Also, because a plurality of surveillance cameras are normally arranged in a department store or shopping center, a large number of watchmen are required to reliably watch many photographed scene images transmitted from the surveillance cameras.
2.3. Second Previously Proposed Art
To prevent a hard burden on the watchman and to prevent the requirement of a plurality of watchmen, not only a photographed scene image is displayed on a monitor of a surveillance center at real time, but also video data indicating the photographed scene image is stored in a video data storing unit arranged in the surveillance center. Therefore, when a watchman placed in the surveillance center requires a specific photographed scene image corresponding to a specific time period, specific video data of the specific photographed scene image is read out from the video data storing unit, so that the specific photographed scene image can be reproduced on the monitor of the surveillance center at any time.
Also, in a remote surveillance system, a surveillance camera is arranged in a surveillance area of the department store or the shopping center, and a monitor is placed in a remote surveillance center placed far from the department store or shopping center. In this case, the surveillance camera is connected to the remote surveillance center through a communication line to perform a remote surveillance operation.
2.4. Problems to be solved by the invention
However, in this remote surveillance system, an upper data transfer rate (or a channel capacity) in the communication line is not sufficient to transmit a large volume of video data indicating the photographed scene image, so that it is difficult to transmit a large volume of video data produced by the surveillance camera to the remote surveillance center at high speed. In this case, there is a problem that a photographed scene image of the surveillance area cannot be displayed at real time.
Also, because it is required that the video data storing unit has a large data capacity to store a large data volume of video data indicating a photographed scene image, it is difficult to arrange the remote surveillance center with the video data storing unit in a small-sized area, and it is difficult to provide the remote surveillance system at a low cost.
A first object of the present invention is to provide, with due consideration to the drawbacks of such a conventional remote surveillance system, a surveillance camera apparatus used for a remote surveillance system, a surveillance apparatus used for the remote surveillance system and the remote surveillance system in which a scene image of a surveillance area photographed by a surveillance camera is easily transmitted from the surveillance camera apparatus to the surveillance apparatus through a communication line having a small channel capacity and is reproduced in the surveillance apparatus at real time to be possible to be viewed by a watchman.
Also, a second object of the present invention is to provide a surveillance camera apparatus used for a remote surveillance system, a surveillance apparatus used for the remote surveillance system and the remote surveillance system in which a burden on a watchman viewing the scene image of the surveillance area is reduced and many watchmen are not required.
The first object is achieved by the provision of a surveillance camera apparatus, comprising:
photographing means for photographing a surveillance area to produce video data indicating a scene of the surveillance area;
video data compressing means for compressing the video data produced by the photographing means at a first compression degree to produce high-compressed video data and compressing the video data at a second compression degree lower than the first compression degree to produce low-compressed video data;
compressed video data storing means for storing the low-compressed video data produced by the video data compressing means;
communication performing means for transmitting the high-compressed video data produced by the video data compressing means to an external apparatus through a communication line to make the external apparatus reproduce a low-definition scene image of the surveillance area at real time or transmitting the low-compressed video data stored in the compressed video data storing means to the external apparatus through the communication line to make the external apparatus reproduce a high-definition past-time scene image of the surveillance area; and
control means for controlling the communication performing means to normally transmit the high-compressed video data and to transmit the low-compressed video data in cases where a request for transmitting the low-compressed video data is received.
In the above configuration, video data is produced by photographing a surveillance area with the photographing means, high-compressed video data is obtained by compressing the video data at a first compression degree, low-compressed video data is obtained by compressing the video data at a second compression degree, and the low-compressed video data is stored in the compressed video data storing means. In this case, the high-compressed video data has a small data volume, and the low-compressed video data has a large data volume. Also, a high-definition scene image is reproduced from the low-compressed video data, and a low-definition scene image is reproduced from the high-compressed video data.
Because a communication line connecting the surveillance camera apparatus and the external apparatus has a small channel capacity, though the high-compressed video data having a small data volume can be transmitted through the communication line at a high speed, it is difficult to transmit the low-compressed video data through the communication line at a high speed. Therefore, the high-compressed video data having a small data volume is normally transmitted to the external apparatus through the communication line under the control of the control means, so that a watchman views a low-definition scene image of the surveillance area reproduced from the high-compressed video data in the external apparatus.
In cases where the watchman desires to view a high-definition scene image of the surveillance area, a request for transmitting the low-compressed video data is sent to the control means, so that the low-compressed video data stored in the compressed video data storing means is transmitted to the external apparatus under the control of the control means. Therefore, the watchman can view a high-definition scene image of the surveillance area reproduced from the low-compressed video data in the external apparatus.
Accordingly, even though a channel capacity of the communication line is limited to a small value, because the high-compressed video data having a small data volume is normally transmitted to the external apparatus through the communication line, the watchman can watch a scene image of the surveillance area at real time.
Also, because the low-compressed video data is stored in the compressed video data storing means, in cases where the watchman desires to view a scene image of the surveillance area at high definition, the low-compressed video data stored in the compressed video data storing means is transmitted to the external apparatus through the communication line at a slow speed, and the watchman can reliably view a scene image of the surveillance area reproduced from the low-compressed video data at a high definition as a past-time image.
It is preferred that the surveillance camera apparatus further comprise:
unusual condition detecting means for detecting an unusual condition occurring in the surveillance area and outputting an unusual condition detecting signal to the control means to transmit the low-compressed video data stored in the compressed video data storing means to the external apparatus in place of the high-compressed video data.
In the above configuration, when an unusual condition occurring in the surveillance area is detected by the unusual condition detecting means, an unusual condition detecting signal is output to the control means. Therefore, the low-compressed video data stored in the compressed video data storing means is transmitted to the external apparatus in place of the high-compressed video data under the control of the control means.
Accordingly, even though the watchman normally views a scene image of the surveillance area at a low definition, the watchman can view a past-time scene image of the surveillance area at a high definition when an unusual condition occurs in the surveillance area.
It is also preferred that the surveillance camera apparatus further comprise:
unusual condition detecting means for detecting an unusual condition occurring in the surveillance area and outputting an unusual condition detecting signal to the control means to transmit the low-compressed video data stored in the compressed video data storing means to the external apparatus in place of the high-compressed video data;
a communication line through which the high-compressed video data produced by the video data compressing means and the low-compressed video data stored in the compressed video data storing means are transmitted to the external apparatus, the communication line being normally set to a communication-impossible condition to prohibit the transmission of the high-compressed video data and the low-compressed video data performed by the communication performing means, and the communication-impossible condition of the communication line being changed to a communication-possible condition by the control means to make the communication performing means transmit the high-compressed video data and the low-compressed video data in cases where the unusual condition detecting signal output from the unusual condition detecting means is received by the control means; and
supplementary video data compressing means for reading out first low-compressed video data produced by the video data compressing means at an occurrence time of the unusual condition detected by the unusual condition detecting means, second low-compressed video data produced by the video data compressing means just before the production of the first low-compressed video data and third low-compressed video data produced by the video data compressing means just after the production of the first low-compressed video data from the compressed video data storing means under the control of the control means and compressing the first low-compressed video data, the second low-compressed video data and the third low-compressed video data to produce specific compressed video data of which a compression degree is the same as that of the high-compressed video data produced by the video data compressing means, in cases where the unusual condition detecting signal output from the unusual condition detecting means is received by the control means, the specific compressed video data being transmitted to the external apparatus by the communication performing means through the communication line set to the communication-possible condition to make the external apparatus reproduce a low-definition past-time scene image of the surveillance area.
In the above configuration, the communication line is normally set to a communication-impossible condition. When an unusual condition of the surveillance area is detected by the unusual condition detecting means, the unusual condition detecting signal is output to the control means, so that the condition of the communication line is changed to a communication-possible condition by the control means. In this case, it takes a prescribed time to change the condition of the communication line to the communication-possible condition. Therefore, the watchman cannot view a low-definition scene image of the surveillance area corresponding to an occurrence time of the unusual condition at a real time.
Also, when the unusual condition detecting signal is output to the control means, first low-compressed video data produced at an occurrence time of the unusual condition, second low-compressed video data produced just before the production of the first low-compressed video data and third low-compressed video data produced just after the production of the first low-compressed video data are read out from the compressed video data storing means and are compressed to specific compressed video data by the supplementary video data compressing means. In this case, a compression degree of the specific compressed video data is the same as that of the high-compressed video data. Thereafter, the specific compressed video data is transmitted to the external apparatus by the communication performing means through the communication line, and a watchman views a low-definition scene image of the surveillance area as a past-time image.
Accordingly, even though the watchman cannot view a low-definition scene image of the surveillance area reproduced from the high-compressed video data at real time because it takes a prescribed time to change the condition of the communication line to the communication-possible condition, because the specific compressed video data is produced from the first low-compressed video data at the unusual condition occurrence time, the second low-compressed video data produced at the time just before the first low-compressed video data and the third low-compressed video data produced at the time just after the first low-compressed video data and is transmitted to the external apparatus, the watchman can view a low-definition scene image of the surveillance area corresponding to a time period including the unusual condition occurrence time as a past-time image.
Also, because a compression degree of the specific compressed video data is the same as that of the high-compressed video data, even though a channel capacity of the communication line is limited to a small value, the specific compressed video data can be transmitted to the external apparatus through the communication line at high speed, so that the watchman can immediately view a low-definition scene image of the surveillance area corresponding to a time period including the unusual condition occurrence time.
It is also preferred for the second object that the photographing means comprise:
a plurality of surveillance cameras for respectively photographing one surveillance area to produce video data indicating a scene of the surveillance area; and
an identification information adding unit for adding identification information to the video data of the surveillance area produced in each surveillance camera to distinguish the video data produced in each surveillance camera from the video data produced in the other surveillance cameras.
In the above configuration, even though a plurality of surveillance cameras are arranged to photograph a plurality of surveillance areas, because identification information is added to the video data produced by each surveillance camera, a watchman can specify the surveillance camera corresponding to a scene image displayed in the external apparatus.
The first and second objects are also achieved by the provision of a surveillance apparatus, comprising:
communication performing means for receiving compressed video data transmitted from a surveillance camera apparatus through a communication line;
compressed video data expanding means for expanding the compressed video data received by the communication performing means to produce video data indicating a scene image of a surveillance area;
displaying means for displaying a scene image of a surveillance area according to the video data produced by the compressed video data expanding means as a real time image;
compressed video data storing means for storing the compressed video data received by the communication performing means as past compressed video data;
instruction receiving means for receiving an instruction for displaying a past-time scene image; and
control means for controlling the compressed video data expanding means, the displaying means and the compressed video data storing means according to the instruction received by the instruction receiving means to stop the expanding of the compressed video data, read out the past compressed video data from the compressed video data storing means, expand the past compressed video data by the compressed video data expanding means to produce past video data and display a past-time scene image of the surveillance area according to the past video data by the displaying means.
In the above configuration, in a normal operation, the compressed video data received by the communication performing means is expanded by the compressed video data expanding means to produce video data, and a scene image of a surveillance area is displayed as a real time image according to the video data by the displaying means.
However, in cases where a watchman desires to view a past-time image of the surveillance area because the watchman misses viewing the scene image of the surveillance area at real time, the watchman inputs an instruction for displaying a past-time scene image to the instruction receiving means. In this case, the expanding of the compressed video data is stopped under the control of the control means, the past compressed video data is read out from the compressed video data storing means under the control of the control means, the past compressed video data is expanded by the compressed video data expanding means under the control of the control means to produce past video data, and a past-time scene image of the surveillance area is displayed according to the past video data by the displaying means under the control of the control means.
Accordingly, a past-time scene image of the surveillance area can be displayed in place of the real time scene image, so that a burden on the watchman can be reduced because it is not required that the watchman always views the scene image displayed at real time.
The first object is also achieved by the provision of a remote surveillance system, comprising:
a surveillance camera apparatus for producing compressed video data indicating a scene of a surveillance area;
a surveillance apparatus for displaying the scene image of the surveillance area according to the compressed video data produced by the surveillance camera apparatus; and
a communication line through which the compressed video data produced by the surveillance camera apparatus is transmitted to the surveillance apparatus, wherein the surveillance camera apparatus comprises:
photographing means for photographing the surveillance area to produce the video data;
video data compressing means for compressing the video data produced by the photographing means at a first compression degree to produce high-compressed video data and compressing the video data at a second compression degree lower than the first compression degree to produce low-compressed video data;
compressed video data storing means for storing the low-compressed video data produced by the video data compressing means; and
communication performing means for transmitting the high-compressed video data produced by the video data compressing means to the surveillance apparatus through the communication line or transmitting the low-compressed video data stored in the compressed video data storing means to the surveillance apparatus through the communication line, and the surveillance apparatus comprises:
communication performing means for receiving the high-compressed video data or the low-compressed video data transmitted from the surveillance camera apparatus through the communication line;
compressed video data expanding means for expanding the high-compressed video data or the low-compressed video data received by the communication performing means to produce expanded video data;
displaying means for displaying a low-definition scene image of the surveillance area according to the expanded video data produced from the high-compressed video data by the compressed video data expanding means as a real time image or displaying a high-definition scene image of the surveillance area according to the expanded video data produced from the low-compressed video data by the compressed video data expanding means as a past-time image;
instruction receiving means for receiving an instruction for displaying a past-time scene image; and
control means for controlling the surveillance camera apparatus to normally output the high-compressed video data compressed by the video data compressing means and to output the low-compressed video data stored in the compressed video data storing means in cases where the instruction for displaying a high-definition scene image is received by the instruction receiving means.
In the above configuration, in the surveillance camera apparatus, video data is produced by photographing a surveillance area with the photographing means, high-compressed video data is obtained by compressing the video data at a first compression degree, low-compressed video data is obtained by compressing the video data at a second compression degree, and the low-compressed video data is stored in the compressed video data storing means. The high-compressed video data is normally transmitted to the surveillance apparatus through the communication line. In the surveillance apparatus, the high-compressed video data is expanded by the compressed video data expanding means, so that a low-definition scene image of the surveillance area is displayed by the displaying means.
Accordingly, even though a channel capacity of the communication line is limited to a small value, because the high-compressed video data has a small data volume, the high-compressed video data can be transmitted to the surveillance apparatus through the communication line at high speed, so that a watchman can view a scene image of the surveillance area at real time.
When the watchman desires to view a scene image of the surveillance area at high definition, the watchman inputs an instruction for displaying a high-definition scene image to the instruction receiving means. In this case, the surveillance camera apparatus is controlled by the control means to output the low-compressed video data to the surveillance apparatus in place of the high-compressed video data, the low-compressed video data is expanded by the compressed video data expanding means, so that a high-definition scene image of the surveillance area is displayed by the displaying means.
Accordingly, the watchman can view a high-definition scene image of the surveillance area as a past-time image when the watchman desires to view a scene image of the surveillance area at high definition.
It is preferred that the surveillance camera apparatus further comprise:
unusual condition detecting means for detecting an unusual condition occurring in the surveillance area; and
control means for controlling the communication performing means to output unusual condition detecting information to the surveillance apparatus in cases where the unusual condition is detected by the unusual condition detecting means, the unusual condition detecting information output by the communication performing means being displayed by the displaying means.
In the above configuration, when the occurrence of an unusual condition is detected by the unusual condition detecting means, unusual condition detecting information is output to the surveillance apparatus under the control of the control means of the surveillance camera apparatus. Therefore, the watchman can notice the occurrence of the unusual condition by viewing the unusual condition detecting information displayed by the displaying means. In this case, because the watchman desires to view a scene image of the surveillance area at high definition, the watchman inputs the instruction for displaying a high-definition scene image to the instruction receiving means, and the watchman views a high-definition scene image of the surveillance area displayed by the displaying means at a past-time image.
Accordingly, the watchman can view the scene image of the surveillance area at high definition when an unusual condition occurs in the surveillance area.
It is preferred for the second object that the surveillance apparatus further comprise:
compressed video data storing means for storing the high-compressed video data received by the communication performing means as past compressed video data, the past compressed video data being expanded to expanded past compressed video data by the compressed video data expanding means in place of the high-compressed video data received by the communication performing means under the control of the control means in cases where an instruction for displaying a past-time scene image is received by the instruction receiving means, and a scene image of the surveillance area reproduced from the expanded past compressed video data being displayed by the displaying means as a past-time image.
In the above configuration, even though the watchman misses viewing a scene image at real time, the watchman can view the scene image at a past-time image. Also, because the high-compressed video data having a small data volume is stored in the compressed video data storing means, a large data capacity is not required for the compressed video data storing means. Therefore, the surveillance apparatus can be made small, and the remote surveillance system can be made at a low cost.
It is also preferred for the second object that the photographing means comprise:
a plurality of surveillance cameras for respectively photographing one surveillance area to produce video data indicating a scene of the surveillance area; and
an identification information adding unit for adding identification information to the video data of the surveillance area produced in each surveillance camera to distinguish the video data produced in each surveillance camera from the video data produced in the other surveillance cameras, the high-compressed video data with the identification information corresponding to each surveillance camera being transmitted from the surveillance camera apparatus to the surveillance apparatus to display a low-definition scene image as a real-time image by the displaying means for each surveillance camera.
In the above configuration, even though a plurality of surveillance cameras are arranged to photograph a plurality of surveillance areas, because identification information is added to the video data produced by each surveillance camera, the high-compressed video data with the identification information corresponding to each surveillance camera being transmitted from the surveillance camera apparatus to the surveillance apparatus. Therefore, a watchman can specify the surveillance camera corresponding to a scene image.